public abstract class FilterSpans extends Spans
Spans implementation wrapping another spans instance,
allowing to filter spans matches easily by implementing accept(org.apache.lucene.search.spans.Spans)| Modifier and Type | Class and Description |
|---|---|
static class |
FilterSpans.AcceptStatus
Status returned from
accept(Spans) that indicates
whether a candidate match should be accepted, rejected, or rejected
and move on to the next document. |
| Modifier and Type | Field and Description |
|---|---|
protected Spans |
in
The wrapped spans instance.
|
NO_MORE_POSITIONSNO_MORE_DOCS| Modifier | Constructor and Description |
|---|---|
protected |
FilterSpans(Spans in)
Wrap the given
Spans. |
| Modifier and Type | Method and Description |
|---|---|
protected abstract FilterSpans.AcceptStatus |
accept(Spans candidate)
Returns YES if the candidate should be an accepted match,
NO if it should not, and NO_MORE_IN_CURRENT_DOC if iteration
should move on to the next document.
|
int |
advance(int target)
Advances to the first beyond the current whose document number is greater
than or equal to target, and returns the document number itself.
|
TwoPhaseIterator |
asTwoPhaseIterator()
Optional method: Return a
TwoPhaseIterator view of this
Scorer. |
void |
collect(SpanCollector collector)
Collect postings data from the leaves of the current Spans.
|
long |
cost()
Returns the estimated cost of this
DocIdSetIterator. |
int |
docID()
Returns the following:
-1 if DocIdSetIterator.nextDoc() or
DocIdSetIterator.advance(int) were not called yet. |
int |
endPosition()
Returns the end position for the current start position, or -1 when
Spans.nextStartPosition() was not yet called on the current doc. |
int |
nextDoc()
Advances to the next document in the set and returns the doc it is
currently on, or
DocIdSetIterator.NO_MORE_DOCS if there are no more docs in the
set.NOTE: after the iterator has exhausted you should not call this method, as it may result in unpredicted behavior. |
int |
nextStartPosition()
Returns the next start position for the current doc.
|
float |
positionsCost()
Return an estimation of the cost of using the positions of
this
Spans for any single document, but only after
Spans.asTwoPhaseIterator() returned null. |
int |
startPosition()
Returns the start position in the current doc, or -1 when
Spans.nextStartPosition() was not yet called on the current doc. |
String |
toString() |
int |
width()
Return the width of the match, which is typically used to compute
the
slop factor. |
doCurrentSpans, doStartCurrentDocall, empty, slowAdvanceprotected final Spans in
protected abstract FilterSpans.AcceptStatus accept(Spans candidate) throws IOException
IOExceptionpublic final int nextDoc()
throws IOException
DocIdSetIteratorDocIdSetIterator.NO_MORE_DOCS if there are no more docs in the
set.nextDoc in class DocIdSetIteratorIOExceptionpublic final int advance(int target)
throws IOException
DocIdSetIteratorDocIdSetIterator.NO_MORE_DOCS if target
is greater than the highest document number in the set.
The behavior of this method is undefined when called with
target ≤ current, or after the iterator has exhausted.
Both cases may result in unpredicted behavior.
When target > current it behaves as if written:
int advance(int target) {
int doc;
while ((doc = nextDoc()) < target) {
}
return doc;
}
Some implementations are considerably more efficient than that.
NOTE: this method may be called with DocIdSetIterator.NO_MORE_DOCS for
efficiency by some Scorers. If your implementation cannot efficiently
determine that it should exhaust, it is recommended that you check for that
value in each call to this method.
advance in class DocIdSetIteratorIOExceptionpublic final int docID()
DocIdSetIterator-1 if DocIdSetIterator.nextDoc() or
DocIdSetIterator.advance(int) were not called yet.
DocIdSetIterator.NO_MORE_DOCS if the iterator has exhausted.
docID in class DocIdSetIteratorpublic final int nextStartPosition()
throws IOException
SpansSpans.NO_MORE_POSITIONS.nextStartPosition in class SpansIOExceptionpublic final int startPosition()
SpansSpans.nextStartPosition() was not yet called on the current doc.
After the last start/end position at the current doc this returns Spans.NO_MORE_POSITIONS.startPosition in class Spanspublic final int endPosition()
SpansSpans.nextStartPosition() was not yet called on the current doc.
After the last start/end position at the current doc this returns Spans.NO_MORE_POSITIONS.endPosition in class Spanspublic int width()
Spansslop factor. It is only legal
to call this method when the iterator is on a valid doc ID and positioned.
The return value must be positive, and lower values means that the match is
better.public void collect(SpanCollector collector) throws IOException
SpansSpans.nextStartPosition(), and before
Spans.NO_MORE_POSITIONS has been reached.collect in class Spanscollector - a SpanCollectorIOExceptionpublic final long cost()
DocIdSetIteratorDocIdSetIterator.
This is generally an upper bound of the number of documents this iterator might match, but may be a rough heuristic, hardcoded value, or otherwise completely inaccurate.
cost in class DocIdSetIteratorpublic final TwoPhaseIterator asTwoPhaseIterator()
SpansTwoPhaseIterator view of this
Scorer. A return value of null indicates that
two-phase iteration is not supported.asTwoPhaseIterator in class SpansScorer.twoPhaseIterator()public float positionsCost()
SpansSpans for any single document, but only after
Spans.asTwoPhaseIterator() returned null.
Otherwise this method should not be called.
The returned value is independent of the current document.positionsCost in class SpansCopyright © 2000-2017 Apache Software Foundation. All Rights Reserved.